Ginseng shows benefit in cancer treatment

CHICAGO - Flaxseed slowed the growth of prostate tumors in men, while ginseng
helped relieve the fatigue that cancer patients often feel, US researchers
reported on Saturday in two of the first scientifically rigorous looks at
alternative medicine.

A seasonal worker holds ginseng rhizomes reaped on a field in
Graefendorf, eastern Germany in May 2007. [Agencies]

The studies reflect doctors'
efforts to explore the risks and benefits of foods and supplements that are
routinely taken by their patients with little scientific proof they help.

Americans spend between $36 billion and $47 billion a year on complementary
and alternative therapies, according to the National Center for Health
Statistics.

"Patients are taking these compounds but we need to know if they are doing
any good or any harm," said Dr. Bruce Cheson of Georgetown University Hospital
in Washington, who led a panel on alternative therapies at a meeting of the
American Society of Clinical Oncology.

In the flaxseed study, researchers at Duke University Medical Center in North
Carolina and colleagues evaluated the seed's role as a food supplement in 161
men who were scheduled to undergo surgery for prostate cancer.

"The growth rate was decreased in the men who got flaxseed," said Dr. Nancy
Davidson, an oncologist at Johns Hopkins University in Baltimore who is
president-elect of ASCO. "I think this is fascinating."

Flaxseed is rich in omega-3 fatty acids and lignans, a fiber found on the
seed coat.

"We were looking at flaxseed because of its unique nutrient profile," said
Wendy Demark-Wahnefried, a researcher in Duke's School of Nursing, who led the
study.

Half of the men in the study added 30 grams of flaxseed daily to their diets
for about 30 days. Half of the flaxseed group also went on a low-fat diet.

After the surgery, the researchers looked at the men's tumor cells to see how
quickly the cancer had multiplied.

The cancer cells in both the flaxseed groups grew about 30 to 40 percent
slower than the control group.

But Demark-Wahnefried is not ready to prescribe flaxseed.

"It's a healthy food. It has a lot of vitamins and a lot of fiber. But we can
not definitively say at this point you should take flaxseed because it is
protective against prostate cancer," she said, adding that flaxseed now needed
to be studied to see if it can prevent prostate cancer.

In the ginseng trial, Debra Barton of the Mayo Clinic in Rochester,
Minnesota, and colleagues tested three different doses of the herb on patients
with a variety of cancers who were expected to live at least six months.

Twenty-five percent of patients taking a 1,000-mg dose and 27 percent of
patients taking a 2,000-mg dose said their fatigue symptoms were "moderately
better" or "much better."

Only 10 percent of those taking a 750-mg dose reported an improvement, which
was about the same as the placebo group.

Patients in the trial took Wisconsin ginseng from a single crop that was
tested for uniform potency. It was powdered and given in a capsule form.

"I wouldn't have predicted this, I have to admit," Davidson said in an
interview. "We might want to test this on a large scale."

The flaxseed study was funded by the National Institutes of Health and the
ginseng study was supported by US Public Health Service
grants.